Autumn arrived late in Washington this year, along with a morbid acceptance that Donald Trump may well get his hands on the nuclear football.

Nothing else Trump has said—about Muslims, women, protesters, immigrants and so on—has chilled the political, military and media establishment more than his glib pronouncements on nuclear weapons. If we’re not going to use them, Trump told MSNBC’s Chris Matthews in a typical remark last March, “then why are we making them?” He said he might drop one on the Islamic State group, known as ISIS, or Europe. “You want to be unpredictable,” he said. A year ago, people thought such statements would disqualify him.

Whether he knew it or not, though, Trump was expressing standard U.S. policy since the dawn of the Cold War. But it’s one thing for President Barack Obama or his mostly even-keeled predecessors to have the nuclear codes. It’s another thing to hand them to a man whose narcissistic, grandiose and impulsive personality “is certainly extreme by any standard, and particularly rare for a presidential candidate,” as the psychologist Dan McAdams, a student of presidential minds, wrote in The Atlantic. A Trump presidency “could be highly combustible,” McAdams added. “He could be a daring and ruthlessly aggressive decision maker who...never thinks twice about the collateral damage he will leave behind.”

The frightening alchemy of Trump’s personality and his casual remarks about using nukes is reminiscent of General Douglas MacArthur, who in 1952 threatened to ride a similar yearning to make America great again into the White House. A darling of right-wing Republicans, MacArthur was a towering hero in both world wars, but President Harry Truman in 1951 had relieved him of command in the depths of the Korean War. The proximate cause was his open insinuation that “defeatists” in Washington, D.C., were keeping him from attacking China with airstrikes—and nuclear weapons, if need be—to break the stalemate, one he had largely created by provoking Beijing into a massive battlefield intervention. Truman, fearing such a move would prompt Russia to come to China’s aid and precipitate World War III, fired him.

MacArthur, unchastened and abetted by Republicans desperate to oust Democrats from the White House after two decades on the outside, came home to a rapturous welcome fit for a Roman general. “Church bells pealed beneath the Bataan ”—MacArthur’s plane—“as the aircraft crossed the country,” author H.W. Brands recounts in a timely new book, The General vs. the President: MacArthur and Truman at the Brink of Nuclear War. At a time when Trump has unnerved liberals and mainstream Republicans alike with his “huge, unbelievable” crowds, it’s worth being reminded that they are nothing compared with the mass adulation MacArthur stirred up.

Douglas Fegenbush, deputy commander of U.S. Marine Corps Forces in South Korea, stands for a minute silence in tribute to the war dead in front of the statue of U.S. General Douglas MacArthur at Freedom Park in Incheon, west of Seoul September 15, 2009. Lee Jae-Won/Reuters

“Cities and towns voted resolutions of gratitude and congratulations,” Brands writes. “Parents named sons for the general.” The town of “Truman, Texas, debated whether to rechristen itself MacArthur.” The turnout for the general in Washington, D.C., was bigger “than for any figure in the history of the nation's capital,” including the victory parades for U.S. troops after World War II or Union brigades after the South’s surrender in 1865, Brands writes. “Half a million men, women and children swarmed the slopes around the Washington Monument and spilled out across the national mall.” Artillery units fired 17-gun salutes, “their concussions giving way to fighter jets streaking overhead.” In his triumphalist address to a joint session of Congress, MacArthur sprung the cheering members from their seats with lines like, “You cannot appease or otherwise surrender to Communism in Asia without simultaneously undermining our efforts to halt its advance in Europe.” In a speech elsewhere, the general darkly hinted that Truman and his advisers had fallen prey to “Marxian philosophy.”

Such sentiments resonate today as America pushes through the second decade of a seemingly endless struggle with Islamic terrorism, not to mention challenges from a newly pugnacious China and Russia. Many Americans, and not just Trump’s uninformed devotees, yearn for tidy, simple and quick endings. They are impatient. They have forgotten, or may never have learned, how a far smarter and worldly man than Trump, a war hero riding a tide of hysterical anti-Communism, brought us to the brink of a nuclear World War III.

MacArthur was “awesomely brilliant,” his contemporary General Omar Bradley once remarked—not something many would say about Trump—“but as a leader he had several major flaws: an obsession for self-glorification, almost no consideration for other men with whom he served and a contempt for the judgment of his superiors.” In short, Bradley said, “MacArthur was a megalomaniac.”

Sounds familiar. Trump also shares MacArthur’s affinity for ethnic stereotypes. For Trump, it’s Mexicans and Muslims. For MacArthur, who spent the bulk of his career in the Far East, it was Asians. Diplomats in Washington “knew nothing of the Asian mind,” he often complained. He advised veteran diplomat Averell Harriman that Americans “hate to die...whereas with Orientals, life begins with death.” According to Harriman’s account, “They die quietly, ‘folding their arms as a dove folding his wings.’” Despite such stereotypical thinking, he airily dismissed Chinese warnings that they were prepared to take heavy casualties to repulse an American thrust to their border.

“Just a continuation of the Red Chinese propaganda line,” an anonymous official told The New York Times. “I don’t think that China wants to be chopped up.” But it would be U.S. troops who were chopped up, when China responded as promised, throwing the Americans back south. MacArthur now proposed taking the war into China itself.

Who knows what the world would look like today had Truman not stood up to MacArthur? Or if MacArthur had captured the White House? The general’s moment would pass after his farewell address to Congress. His 1952 bid for the presidency collapsed at the Republican convention in Chicago. Shorn of his four-starred uniform, his hair gone gray, the 72-year-old delivered a speech whose usual applause lines about total victory and appeasement fell flat. “What they saw, once the euphoria of the initial greeting faded,” Brands writes, “was an old man in mufti who couldn’t find the rhythm of his audience.” MacArthur’s bid to harness the raging anti-Communist fervor had failed. The party was looking for a vision of a prosperous, postwar future, not a ghostly reprise of the past.

And the delegates had another war hero to turn to, Dwight D. Eisenhower, the master commander of Allied forces for the invasion of Nazi-occupied France. “Ike” was the aloof MacArthur’s antithesis. He “had the common touch,” Brands writes. “His grin could light up a room or an arena…. His smile might beam brilliantly even as his blue eyes coolly calculated his next step.” And he promised to “go to Korea” and end the war. He swamped Democratic candidate Adlai Stevenson. In 1953, a change of Kremlin leadership led to a negotiated Korean settlement.

Years later, Eisenhower would claim he “discretely” threatened the Soviets and Chinese with nuclear war if they didn’t force North Korea to sign an armistice. Truman, it turns out, had prepared a nuclear strike too. Whatever the merit of Eisenhower’s claim, both presidents benefitted from their cool determination, patience and quiet diplomacy.

This year, there was no Eisenhower to extinguish the nativist mobs stirred up by Trump, whose ignorance and impulsiveness make MacArthur look like Mahatma Gandhi. And in their pining to “make America great again,” it’s not clear that the Republican challenger and his glib minions understand things have changed since 1952, when MacArthur assured Congress that America’s military power was “big enough to handle the situation in the Far East without serious detriment” to the defense of Europe.

Truman and his advisers thought the egomaniacal MacArthur had become unmoored. Six decades later, only the most die-hard anti-Communists would say that a wider war in China was a good idea. Today, a far stronger China and an opportunistic Russia are in no mood to succumb to American threats. If a Commander-in-Chief Trump pushes the world to the nuclear brink, even some of his most slavish aides may regret what they’ve wrought and beg a real general to take charge.